Electric furnace



C. H. CARPENTER.

I ELECTRIC FURNACE.

' APPLICATION FILED AUG-6.1920. I I 1 409 9 Patented Mar. 14, 1922.

v I INVENTOR 7 Cramzoz: 12f Carpejmr o I BY W5. WW I I ATTORNEY material.

"material. The outside portions of the walls" UNITED emf-res mrsurorrics.

oRANsToiv 1i. onnrnnrnn,or mwnifrEnNsY vAniA, nssrenon TO'WESTINGHQ-USE ELECTRIC & MANUFACTURING COMPANY, A ooRPonA'rron or PENNSYLVANIA.

ELECTRIC FURNACE,

Specification of Letters Patent. 7 Patent-ed mj l 14 1922 Application filed Auguste, 1920. Serial 110.401,??9.

To aZZ-wiwmit may concern:

Be it known that I, CnANsToN H. time rnN'rnR, a citizen of the-United States, and

resident oflrwin, in the county of Westmoreland and State of Pennsylvania, have One object of my invention is to provide an electric furnace of the above-indicated type that shallbe efficient and economical in operation and that shall be provided with easily removable conducting lugs for connecting the receptacle to be heated to the source of energy.

Inan electric furnace constructed in accordance with my invention,'a crucible, com

posed of any suitable conducting material, such as a mixture of graphiteand clay, 1S surrounded bywalls composed of refractory Within such walls-are located two compartments containing finely divided conducting material which is'connected to the contact terminals of the electric circuit through which energy is supplied to the furnace. Two lugs are detachably connected to the crucible and extend into the compartments containing the-powdered conducting surrounding the crucible are preferably com posed of some suitable heat-insnlating 1naterial.

In the accompanying drawing, Figure 1 is a plan view and Fig, 2 is a sectional clove: tional View of an electric furnace construct ed in accordance with my invention Referring to the drawing, a crucible l, which is composed of any suitable conduc ing material, such as a mixture of graphite and clay, is provided with projections 53 and 3. The crucible is surrounded by walls 4 having inside surfaces composed of any suitable refractory material. An opening 5 is formed in the front wall for permitting the pouring of the material contained within the crucible. surrounding the crucible 1 are prefcrablv composed of any suitable heat-insulating material.

The outside portions of the walls Two compartments 6 and7 are formed in the wall surrounding the crucible and contain powdered conducting material as,'for example, finely divided graphite. The contact terminals 8' and 9 of the electric circuit connectedto the furnace are disposed inthe bottom of the compartments 6 and T. Pressed coke electrodes 1(la1id'11'are'provided for connecting such contactterminals to the =ii nely divided conducting material contained within the compartments 6 and T.

Two lugs 12and 13, which project into the 1 compartmentsfi and 7, are detachably connected, in anysuitable manner, to the projections 2 and3 .on the sides of the crucible 1. Preferably, threaded extensions 14 and 15 areprovided for connecting the lugs 12 and '13 to the projections Q-and 3.

Trunnions 16 and 17 are mounted on the outside portions of the furnacefor permitting the tilting of such furnace to pour the :material contained within the crucible 1.

In operating the furnace, electric current is transmitted from the contact terminal 8, through the block 11, the powdered conducting material contained within the com-' partment 7, lug 13, projection 3, crucible 1, projection 2, lug 12, the powdered conducting material contained within the compartment 6, and block 10, to the contact terminal 9. The passage of current through the crucible 1 evenly heats such crucible for melting the material contained within it. The powdered conducting material contained 'within the compartments 6 and 7 is very easily renewed and, moreover, the lugs 12 and 13, which connect the crucible to such powdered conducting material, are easily renewed without renewal of a complete crucible.

Modifications in the furnace and in the arrangement and location of parts may be made within the spirit and scope of my in-' vention, and such modifications are intended to be covered by the appended claims.

I claim as my invention z-- 1. In an electric furnace, the combination with a crucible having two projections extending therefrom, of lugs detachably connected to said projections and extending into compartments containing granular material.

2. In an electric furnace, the combination comprising a crucible having detachable lugs connected thereto, granular conducting material surrounding the ends of said lugs. and contact terminals connected to said granular material.

3. In an electric furnace the combination comprising a crucible having lugs threadably connected to it, compartments containing granular graphite surrounding the ends of said lugs, and contact terminals in circuit with said granular graphite.

4. In an electric furnace, the combination with a crucible composed of conducting ma terial, Walls of refractory material surrounding said crucible and two projecting portions extending from said crucible, of two lugs detachably connected to the projections on said crucible and projecting through said refractory Walls into compartmentscontaining granular graphite, and terminal conductors connected to the graphite in said compartments.

5. In an electric furnace, the combination With a crucible composed of conducting material and having projections extending therefrom, of lugs detachably connected to said projections and extending into conipartments containing granular conducting material.

6. In an electric furnace the combination with a crucible composed of. conducting material and having tWo projections extending therefrom, and a refractory Wall surrounding said crucible, of two compartments in said Wall containing finely divided conducting material, lugs detachably connected to said projections and extending into said compartments, and terminal conductors connected to the conducting material contained in said compartments.

In testimony Whereo't I have hereunto subscribed my name this 30th day of July,

CRANSTON H. CARPENTER. 

